1. Field of Invention
The present invention relates to a bumper stopper integrated with a dust cover. More particularly, it relates to a bumper stopper integrated with a dust cover in which a bumper stopper constituting a shock absorber by using a material comprising thermoplastic ether ester (TPEE) elastomer, and a dust cover which covers the bumper stopper are integrally molded.
2. Description of Related Art
A shock absorber is an anti-vibration and shock absorbing device which is installed between an axle and a body of a vehicle and absorbs vibration or shock on the axle transmitted from the road surface to enhance passenger's ride comfort when the vehicle is driven. As illustrated in FIG. 1, a typical shock absorber includes a piston rod, a bumper stopper fixed and mounted on the upper portion of the piston rod, a dust cover which covers the piston rod and the bumper stopper, a damper part through which the piston rod is installed, and a cup which covers an upper portion of the damper part.
The bumper stopper serves to absorb shock and vibration inputted through the shock absorber when rebound occurs to the vehicle. For this purpose, in the bumper stopper, the energy absorption ratio needs to be extremely high, and long-term fatigue durability performance due to compressive deformation needs to be secured. Further, the bumper stopper needs to have a small rate of change in characteristics before and after the durability, and not incur a strange sound/noise during the operation.
Typically, urethane foam is applied as a material for a bumper stopper. The urethane foam has excellent energy absorption capability and excellent compressive deformation characteristic and durability, and thus is applied to most of the vehicle. However, the urethane foam is disadvantageous in being limited in grade which is applicable as a material for a bumper stopper and very expensive. Further, since hydrolysis due to moisture, generation of noise caused by freezing when moisture flows in during the cold spell, and an abrasion phenomenon caused by foreign materials such as sand occur in the urethane foam, it may be essential to install a dust cover in order to prevent the phenomenon. In addition, noise is likely to occur due to permeation of air between the cell structures and blow to a cup on the upper portion during compression and strain.
The information disclosed in this Background section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.